Field of the Invention
The present invention relates to mobile communication.
Related Art
3rd generation partnership project (3GPP) long term evolution (LTE) evolved from a universal mobile telecommunications system (UMTS) is introduced as the 3GPP release 8. The 3GPP LTE uses orthogonal frequency division multiple access (OFDMA) in a downlink, and uses single carrier-frequency division multiple access (SC-FDMA) in an uplink.
Such LTE may be divided into a frequency division duplex (FDD) type and a time division duplex (TDD) type.
As set forth in 3GPP TS 36.211 V10.4.0, the physical channels in 3GPP LTE may be classified into data channels such as PDSCH (physical downlink shared channel) and PUSCH (physical uplink shared channel) and control channels such as PDCCH (physical downlink control channel), PCFICH (physical control format indicator channel), PHICH (physical hybrid-ARQ indicator channel) and PUCCH (physical uplink control channel).
Meanwhile, since a larger number of recent communication devices demand much larger communication capacity, efficient utilization of finite frequency resources is getting more and more important in the next generation wireless communication system. Even a cellular communication system such as the LTE system considers using a unlicensed band such as the 2.4 GHz band employed for the existing WLAN systems or a unlicensed band such as the 5 GHz band for traffic offloading. The use of the LTE communications technology in the unlicensed band is called LTE-U.
Aside from the fact that a specific LTE-U based cell is interfered by a different LTE-U based cell, the specific cell may receive interference from a WLAN-based AP and STA.
Therefore, there needs a method for measuring such interference.